leave it original or replace parts?

[1776-1976-Eldo]

Checked my radiator, and it is a 3 core, so its originality is in question already. Was there a 3 core on a 76 Eldo? It looks pretty crusty inside, so a flush should help. I have been driving it a bit and no more boil overs, but I have not pushed it on the highway in the heat either.

[James Landi]

John,

You're correct that your motor will operate at an acceptable temperature range with a compromised/plugged radiator core.  Placed in to service by requiring more stressful heat producing loads, the internal temperature creeps up, and if not caught it time, all hell breaks loose.  I sincerely hope that you're able to sort out the highest capacity cooling solution for your beautiful car.  Someone in the club will know just what you need.   James

[hornetball]

I "think" Eldos came with both 3 and 4-cores (HD cooling).  For Dallas area cruising with AC, 4-core is the way to go.

I swear by Evapo-Cure to clean up rust in a cooling system, but you really have to flush a lot to clear it out of the cooling system after use.  That's a challenge on the Eldo as we don't have access to both engine drain plugs (blocked by transmission).  Evapo-Cure is a rust converter product rather than the normal acid-based flush (same company that makes Evaporust).

[cadlove]

Ok, radiators. Here's a picture of my '78 Seville radiator, smaller than the Eldorado radiator. It's three cores and 32 rows deep. I would suggest yours should be at least that to be right. The parts book shows the Eldorado radiator costing more than the Seville? Bigger?

Having a re-core truly gets full water flow and full air flow cooling. Often expensive but your car is so much better for it.

Regarding (James) buying lovely low mileage cars, it's commonly thought being a time capsule means jumping in them and driving off into the sun-set. Think like this, superb paint, chrome and interiors, great, nothing like them. But everything rubber on the car is 40+ years old?

So, rubber brake hoses, fuel hoses, radiator and heater hoses, seals in brake calipers and cylinders, replace them all. The other question often not raised is if the car is 45 years old and only 23,000 miles on it, how many years could it have stood idle? If we follow the book, engine coolant should be flushed clean every two years? If we continue, brake fluid should be flushed about the same time. Many of these things never get done. If you have a beautiful low mileage original Cadillac I say do them now. 

[Steve W]

I have a 68 CdV, and I had overheating issues, even after replacing the fan with a 7 blade and replacing the water pump. I did a TON of research. and realized that the best option was to get the original 3 row radiator re-cored.
After all, the original radiator worked for over 50 years, so why tamper with Cadillac engineering!

Found this GREAT shop in Burbank, he replaced all the hoses, replaced thermostat and cap, cleaned all the lines, flushed the entire system, re-cored and then re-painted the radiator...all for about 600.00.

That was five years ago. The temp gauge has not moved past the 1/4 mark, even on the frequent 100*+ days here in So Cal. Couldn't be happier!
However, the 7 blade HD fan is a little louder at speed than the stock fan. LOL! I actually could go back to the original fan now if I want to (I save all my old parts too!) but I'm leaving well enough alone.

[1776-1976-Eldo]

Thought I would circle back and provide the solutions I came up with. On the overheat issue, it came down to just replacing the cap, drove it on the highway about 30 miles in 100 degree heat, and no issues. I will still clean the radiator out later, as I do not like the visible crust I can see.

On the alternator issue, I picked up a rebuild kit and rebuilt the one I originally took off. I did find that the Rectifier was bad in it as I tested each part I was replacing. Figured I would put it back on since the "new" rebuilt one had the dim generator light issue. My original worked great once back on. As I tested the "new" rebuilt one, I found the diode trio had one diode bad, so I used the one from the original alternator, now I have 2 fully working alternators. Just rebuild your own, it is cheaper and more fun.